Tractor loader



Sept. 2 1970 L. H. CHANT 3,529,740

TRACTOR LOADER n Filed June 17, 1968 a Sheets-Sheet i W zmwzx ATTORNEY p 22, 1970 y L. H. CHANT 3,529,740

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TRACTOR LOADER Filed June 17, 1968 V 3 Sheets- Sheet 3 INVEA TL R (ea/2am H. [/zan i BY 2 66 .7 9 4M ATTOR N EY United States Patent TRACTOR LOADER Leonard H. Chant, Euclid, Ohio, assignor to General Motors Corporation, Detroit, Mich., a corporation of Delaware Filed June 17, 1968, Ser. No. 737,424 Int. Cl. E02f 3/28 US. Cl. 214-774 Claims ABSTRACT OF THE DISCLOSURE A tractor loader having a material handling bucket pivotally supported at its lower forward end by a bucket carrier. Lift arm means extend between the tractor frame and the bucket carrier and support a primary tilt linkage for tilting the bucket and carrier as a unit relative to the boom. The carrier is provided with a secondary tilt linkage which serves to move the bucket relative to the carrier about a second pivot connection so that selective pivotal movement of the bucket can be obtained about two pivotal connections to thereby provide an increase in dumping height when required.

The conventional front end loader has a lift arm, the extreme forward end of which supports a material handling bucket. A tilt linkage is usually mounted on the lift arm and connected to the rear of the bucket for pivoting the latter about its pivotal support with the lift arm so as to position the bucket during loading and pumping operations or while material is being hauled from one area to another.

In loaders of the above-described type, the dumping height of the bucket is determined in part by the stroke of the lift cylinders and the length of the lift arm and is represented by the maximum clearance under the bucket cutting edge when the bucket is in the fully raised dump position. In addition, most loaders are designed to have a dumping height equal to the average truck body loading height, however, there are times when it may be necessary to have the loader working at a level lower than the truck or the truck may be equipped with Sideboards to increase its payload. In such cases, a loader having capabilities for increased dumping height is desirable in order to compensate for the increase in the effective elevation of the truck body.

Accordingly, the objects of the present invention are to provide a tractor loader having a bucket supported for selective pivotal movement about two pivotal connections, one of which provides an increase in dump height; to provide a tractor mounted material handling bucket that is supported at its lower forward end by a bucket carrier and is selectively movable relative to the carrier in cases where increased dumping height is required and may be pivoted with the carrier as a unit during a normal digging operation; to provide a bucket carrier that is supported by the usual lift arm of a tractor loader and has a'bucket pivotally mounted thereto, the movement of which can be controlled by tilt linkage carried by the carrier; to provide a tractor loader having a lift arm which supports a bucket carrier and incorporates two independently operable tilt linkages which control movement of a bucket supported at its lower forward end by the bucket carrier; and to provide a bucket carrier which is pivotally supported by the forward end of the usual lift arm of a tractor loader and has an independently operable tilt linkage including a bellcrank and link supported by the carrier for moving the bucket relative thereto so as to provide forward pivotal movement of the bucket about a point located forwardly of the usual pivotal connection between the lift arm and bucket.

Patented Sept. 22, 1970 Other objects and advantages of the present invention will be apparent from the following detailed description when taken with the drawings in which:

FIG. 1 shows a tractor loader having a bucket carrier and bucket connected with a lift arm and tilt linkage in accordance with the invention;

FIG. 2 is an enlarged view with one side wall of the bucket removed so as to show in detail the bucket carrier and associated tilt linkage for moving the bucket relative to the carrier;

FIG. 3 shows the loader lift arm of FIG. 1 in a raised position and illustrates the relative positions assumed by the various members of the tilt linkage controlling movement of the bucket;

FIG. 4 is a view similar to FIG. 3 but shows the bucket in the dump position under control of the tilt linkage carried by the bucket carrier;

FIG. 5 shows a modified form of the bucket tilt linkage carried by the carrier;

FIG. 6 shows the relative positions of the members of the tilt linkage of FIG. 5 when the bucket is in the dump position; and

FIG. 7 shows the bucket tilt linkage of FIGS. 1 through 4 operating an Iejector incorporated with the bucket.

Referring to the drawings and particularly FIGS. 1 and 2 thereof, a rubber-tired tractor loader 10 is shown supported by axially spaced front and rear wheels 12 and 14, and including a body frame 16 having an operators station 18. The forward end of the body frame 16 supports a boom or lift arm 20 at a pivotal connection 22 for movement about a transverse horizontal axis under the control of a double-acting hydraulic lift cylinder 24 pivotally mounted between the body frame 16 and lift arm 20 at pivot connections 26 and 28. The forward extreme end of the lift arm 20 supports a generally L-shaped bucket carrier 30 for pivotal movement about a transverse horizontal axis passing through the pivot connection 32. Primary tilt linkage 34 carried by the lift arm 20 serves to control movement of the bucket carrier 30 about the pivot connection 32 during the normal work cycle of the tractor loader. A material handling bucket 36 having the usual laterally spaced side walls 38, a back wall portion 40, floor portion 42 and cutting edge 44 is pivotally supported by the bucket carrier 30 and adapted to move relative to the latter about a transverse horizontal axis passing through the pivotal connection 46. Control of the latter-described movement is provided by a secondary tilt linkage 48 mounted on the bucket carrier 30.

The primary tilt linkage 34 includes a double-acting hydraulic cylinder 50, a reversing lever 52, a pair of links 54 and 56, and a lever 58 which are pivotally interconnected in a manner so as to provide movement of the bucket carrier 30 upon expansion or contraction of the cylinder 50. More specifically, the hydraulic cylinder has the cylinder end thereof pivotally connected to the body frame 16 at a point 60 and the rod end pivotally connected to the upper end of the reversing lever 52 at a point 62. The reversing lever 52 has an intermediate part thereof pivotally connected to the lift arm 20 at a point 64 and the lower end pivotally connected to one end of the link 54 at a point 66. The link 54 extends forwardly for pivotal connection at point 68 with the lever 58 which in turn has the lower end pivotally connected to the lift arm 20 at a point 70 and the upper end pivotally connected at point 72 to the rear end of the link 56, while the forward end of the latter is pivotally connected to the carrier 30 at a point 74.

Thus, it should be apparent from the above that by expanding the hydraulic cylinder 50, the carrier 30 and associated bucket 36 can be rotated rearwardly or clockwise about the pivotal connection 32. Conversely, by contracting the hydraulic cylinder 50 the bucket carrier 30 can be rotated forwardly or in a counterclockwise direction about the pivotal connection 32. It will also be understood that the geometry of the primary tilt linkage 34 is such that when the lift cylinder 24 is expanded so as to raise the lift arm to the dump position, the bucket carrier and the various members of the linkage automatically assume the positions as shown in FIG. 3 at which point contraction of the hydraulic cylinder causes the carrier 30 to rotate counterclockwise about the pivotal connection 32 and dump the load in the bucket 36. As alluded to hereinbefore, however, there are instances when an increased dumping height is required and, to this end, the bucket carrier 30 is provided with the secondary tilt linkage 48 which permits the bucket 36 to move about the pivotal connection 46 relative to the carrier 30 in a counterclockwise direction as shown in FIG. 4. In this regard, and as best seen in FIGS. 2, 3 and 4, it will be noted that the secondary tilt linkage 48 includes a doubleacting hydraulic cylinder 76 which has its cylinder end pivotally connected to the carrier 30 at a point 78. The rod end of the cylinder 76 is pivotally connected to one arm of a lever or bellcrank 80 at a point 82. The bellcrank 80 in turn is pivotally mounted on the carrier 30 at a point 84 and has the other arm pivotally connected at a point 86 to an arcuate link 88, the upper end of which is pivotally connected to the bucket back wall portion 40 at a point 90. Thus, as seen in FIG. 4, by expanding the hydraulic cylinder 76, the bellcrank 80 is rotated about its pivotal support point 84 with the carrier 30 in a clockwise direction causing the lower end of the link 88 to move upwardly from its position in FIG. 2 and cause rotation of the bucket 36 about its pivotal connection 46 with the carrier 30.

At this juncture, it should be mentioned that the drawings show only one side of the vehicle and therefore it will be understood that the linkage described above has corresponding and identical parts located on the other side of the vehicle.

FIG. 5 shows a modified form of the secondary linkage 48 disclosed in FIGS. 1 through 4 and except for the carrier and associated linkage, the parts and components corresponding to those shown in the latter-mentioned figures are identified by the same reference numerals. In this case, a double-acting hydraulic cylinder 92 has the cylinder end pivotally connected to the upper end of a generally C-shaped bucket carrier 94 at a point 96. The rod end of the cylinder 92 extends rearwardly for pivotal connection at a point 97 with the upper end of a lever 98 having an intermediate portion thereof pivotally connected at a point 99 to the carrier 94. The lower end of the lever 98 is pivotally connected at a point 100 to one end of a link 101, the other end of which extends forwardly and upwardly for pivotal connection at a point 102 with the rear of the bucket 36. As shown in FIG. 6, when the hydraulic cylinder 92 is expanded, the lever 98 rotates in a clockwise direction about its pivotal point 99 with the carrier '94 and causes the link 101 to move upwardly and forwardly so as to pivot the bucket 36 about its forward pivotal connection 46 with the carrier 94 in a manner similar to the arrangement as disclosed in FIGS. 1 through 4.

The bucket and carrier combination of FIG. 7 differs from the arrangement shown in FIGS. 1 through 4 only in that the side walls 38 of the bucket are rigidly fixed to the carrier 30 and intended to remain stationary therewith while the back wall portion 40', floor portion 42', and cutting edge 44' are formed as a unit pivotally supported at the forward end of the carrier 30 at pivotal connection 46 and serve as an ejector for discharging material when moved from the phantom line position to the full line position. In all respects, the primary and secondary linkages 34 and 48 are the same as those incorporated with the loader shown in FIG. 1 and operate in a similar fashion.

Various changes and modifications can be made in thi construction without departing from the spirit of the invention. Such changes and modifications are contemplated by the inventor and he does not wish to be limited except by the scope of the appended claims.

I claim:

1. In combination with a tractor mounted material handling bucket including an integrally formed back Wall and floor portion pivotally supported adjacent its lower forward end by a bucket carrier and having a boom for raising the bucket carrier from the ground and first tilt linkage and second tilt linkage for respectively tilting the bucket and carrier as a unit relative to the boom and tilting the back wall and floor portion relative to the carrier, said second tilt linkage supported by said carrier and comprising a lever member having an intermediate portion thereof pivotally mounted on the carrier by a pivotal connection, a link having one end pivotally connected to the lever member at a first pivot point spaced below said pivotal connection and having the other end pivotally connected to an upper portion of the bucket, and a doubleacting hydraulic cylinder pivotally connected between said carrier and a second pivot point on said lever member spaced from said pivotal connection and said first pivot point for rotating the lever member about said pivotal connection whereby said back wall and floor portion is tilted forwardly relative to the carrier to a dump position.

2. The combination of claim 1 wherein said bucket includes a pair of laterally spaced side walls rigidly connected to said back wall and floor portion.

3. The combination of claim 1 wherein said bucket includes a pair of laterally spaced side walls rigidly connected with said carrier.

4. In combination with a tractor mounted material handling bucket pivotally supported adjacent its lower forward end by a bucket carrier and having a boom for raising the bucket carrier from the ground and first tilt linkage and second tilt linkage for respectively tilting the bucket and carrier as a unit relative to the boom and tilting the bucket relative to the carrier, said bucket carrier having a forwardly extending portion which serves to pivotally support the bucket, an upwardly extending portion rigid with said forwardly extending portion, said second tilt linkage carried by said upwardly extending portion and comprising a lever member having an intermediate portion thereof pivotally mounted on the carrier by a pivotal connection, a link having one end pivotally connected to the lever member at a first pivot point spaced below said pivotal connection and having the other end pivotally connected to an upper portion of the bucket, and a hydraulic cylinder pivotally connected between said carrier and a second pivot point on said lever member spaced from said pivotal connection and said first pivot point for rotating the lever member about said pivotal connection whereby said link is raised to cause the bucket to tilt forwardly relative to the carrier to a dump position.

5. In combination with a tractor mounted material handling bucket pivotally supported adjacent its lower forward end by a bucket carrier and having a boom for raising the bucket carrier from the ground and first tilt means and second tilt means for respectively tilting the bucket and carrier as a unit relative to the boom and tilting the bucket relative to the carrier, the improvement wherein said carrier is generally C-shaped in configuration and said second tilt means comprising a lever member having an intermediate portion thereof pivotally mounted on the carrier by a pivotal connection, a link having one end pivotally connected to the lever member at a first pivot point spaced below said pivotal connection and having the other end pivotally connected to an upper portion of the bucket, and a hydraulic cylinder pivotally connected between said carrier and a second pivot point on said lever member located above said pivotal connection for rotating the lever member about said pivotal connection whereby said link is raised to cause the bucket to tilt forwardly relative to the carrier to a dump position.

6. In combination with a tractor mounted material handling bucket pivotally supported adjacent its lower forward end by a bucket carrier and having a boom for raising the bucket carrier from the ground, said bucket carrier having a forwardly extending portion which serves to pivotally support the bucket, an upwardly extending portion rigid with the forwardly extending portion, first tilt linkage mounted on the boom for tilting the bucket and carrier as a unit relative to the boom, second tilt linkage mounted on the carrier for tilting the bucket relative to the carrier, said second tilt linkage comprising a lever member having an intermediate portion thereof pivotally mounted on said upwardly extending portion of the carrier by a pivotal connection, a link having one end pivotally connected to the lever member at a first pivot point spaced below said pivotal connection and having the other end pivotally connected to an upper portion of the bucket, and a hydraulic cylinder pivotally connected between said carrier and a second pivot point on said lever member spaced to one side of a line passing through the centers of said pivotal connection and said first pivot point, said hydraulic cylinder adapted to rotate the lever member about said pivotal connection whereby said link is raised to cause the bucket to tilt forwardly relative to the carrier to a dump position.

7. The combination of claims 6 wherein the longitudinal center axis of said hydraulic cylinder is substantially normal to the line passing through the centers of said pivotal connection and the first pivot point between the lever member and the link when the bucket is in the carry position.

8. The combination of claim 6 wherein the longitudinal center axis of said hydraulic cylinder is substantially normal to the line passing through the centers of said pivotal connection and the first pivot point between the lever member and the link when the bucket is in the dump position.

9. The combination of claim 6 wherein said second pivot point is located at a level below the level of the pivotal connection supporting the lever member when the bucket is in a carry position. I

10. The combination of claim 6 wherein the bucket carrier is generally L-shaped.

References Cited UNITED STATES PATENTS FOREIGN PATENTS 156,465 10/1962 U.S.S.R.

HUGO O. SCHULZ, Primary Examiner US. Cl. X.R. 214-778 

